Typically, an automatically dimming electro-optic interior rearview mirror assembly, such as an electrochromic interior rearview mirror assembly or the like, includes a mirror reflective element that is at least partially received in a casing, sometimes with a bezel portion of the casing snapped to or integral with the rest of the casing/housing so that the bezel portion of the casing overlaps or encompasses a perimeter edge of the reflective element and overlaps on/encroaches onto a portion or perimeter region of an outer or front surface of the reflective element (the surface facing the driver of the vehicle when the mirror assembly is normally mounted in the vehicle). The reflective element is adjustable by the driver to adjust the rearward field of view provided by the mirror reflective element.